Citation

Abstract

Two-dimensional wind tunnel tests were conducted to
determine the aerodynamic effects of spoiler hingeline
location on the NACA 23024 airfoil . The particular
motivation for these studies is potential application of
spoilers for overspeed control of wind turbines .
For the tests, 10% chord spoiler at 90 degrees angle
of deflection and 20% chord spoiler at 60 , 90, and 120
degrees angles of deflection were used. The locations of
attachment for these spoilers were at 10, 20, 30 , 40, 60
and 80 percent along the wing chord. The wind tunnel tests
were conducted at Reynolds numbers of 0.6xlo 6 and of
1.0x10 6 , which correspond to Mach numbers of 0.1 and 0 . 2,
respectively .
Results of the study show that when the spoiler
hingeline is relocated toward the leading edge of the
airfoil, the spoiler effectiveness in producing reduced
lift and added drag is increased , especially at high angles
of attack below the stall . The leading edge suction force
is decreased as the spoiler hingeline is relocated toward
the leading edge of the airfoil. The trend of the results
agrees with theoretical predictions.
It is recommended that tests of spoilers be conducted
on a rotating blade.